The catalytic activity of faujasite type NaY catalysts prepared from local clay (kaolin) with different Si/Al ratio was studied using cumene cracking as a model for catalytic cracking process in the temperature range of 450-525° C, weight hourly space velocity (WHSV) of 5-20 h1, particle size ≤75μm and atmospheric pressure. The catalytic activity was investigated using experimental laboratory plant scale of fluidized bed reactor.
It was found that the cumene conversion increases with increasing temperature and decreasing WHSV. At 525° C and WHSV 5 h-1, the conversion was 42.36 and 35.43 mol% for catalyst with 3.54 Si/Al ratio and Catalyst with 5.75 Si/Al ratio, respectively, while at 450° C and at the same WHSV, the conversion was decreased to 29.15 and 21.86 mol% respectively, and the catalyst of 5.75 Si/Al ratio gave the higher cumene activity than the catalyst with 3.54 Si/Al ratio.
The research aims to find out the impact of cognitive strategies in the mathematical competence of the students of the fourth scientific in the preparatory mahmoudiyah in the Directorate General of The Education of Karkh 2. A post-test of the mathematical competence prepared by (Jassim, 2018) was applied to the sample of (65) students, distributed into two groups of (33) students as experimental group and (32) students as a control group. The results found there are significant differences between the experimental group and the control group in testing the mathematical competence of students for the experimental group.
The current study examined the impact of using PowerPoint presentation on EFL student’s attendance, achievement and engagement. To achieve the aim of this study, three null hypotheses have been posed as follows: There is no statistically significant difference between the mean score of the experimental group attendance and that of the control one; there is no statistically significant difference between the mean score of the experimental group achievement and that of the control one, and there is no statistically significant difference between the mean score of the experimental group engagement and that of the control one. To verify a hypothesis, a sample of sixty students is chosen randomly from the third year, department of English,
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Activated carbon prepared from date stones by chemical activation with ferric chloride (FAC) was used an adsorbent to remove phenolic compounds such as phenol (Ph) and p-nitro phenol (PNPh) from aqueous solutions. The influence of process variables represented by solution pH value (2-12), adsorbent to adsorbate weight ratio (0.2-1.8), and contact time (30-150 min) on removal percentage and adsorbed amount of Ph and PNPh onto FAC was studied. For PNPh adsorption,( 97.43 %) maximum removal percentage and (48.71 mg/g) adsorbed amount was achieved at (5) solution pH,( 1) adsorbent to adsorbate weight ratio, and (90 min) contact time. While for Ph adsorption, at (4) solution pH, (1.4) absorbent to adsorbate weight ratio, and (120 min) contact
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The goal of this investigation is to prepare zinc oxide (ZnO) nano-thin films by pulsed laser deposition (PLD) technique through Q-switching double frequency Nd:YAG laser (532 nm) wavelength, pulse frequency 6 Hz, and 300 mJ energy under vacuum conditions (10-3 torr) at room temperature. (ZnO) nano-thin films were deposited on glass substrates with different thickness of 300, 600 and 900 nm. ZnO films, were then annealed in air at a temperature of 500 °C for one hour. The results were compared with the researchers' previous theoretical study. The XRD analysis of ZnO nano-thin films indicated a hexagonal multi-crystalline wurtzite structure with preferential growth lines (100), (002), (101) for ZnO nano-thin films with different thi
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Compounds of (ZnO)1-x(SnO 2 ) x were prepared with various proportions of tin oxide (SiO 2) (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) by mixing zinc oxide (ZnO) with highpurity tin oxide and then sintering the mixture in an oven at a temperature of 1000 °C for a period of 1 h. The resulting powders were ground and pressed into tablets of 1 cm diameter and 0.5 cm thickness. The properties of (ZnO) 1-x(SnO 2 ) x composites flms were prepared and studied as sensitive to the diferent gases NO2 and H2 S. Thin flms were prepared from (ZnO) 1-x(SnO 2 ) x via pulsed laser deposition method using glass and single crystal silicon for investigation the morphology and gas sensing properties with a thickness of 150 nm. The morphology examinat
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Pure and Fe-doped zinc oxide nanocrystalline films were prepared
via a sol–gel method using -
C for 2 h.
The thin films were prepared and characterized by X-ray diffraction
(XRD), atomic force microscopy (AFM), field emission scanning
electron microscopy (FE-SEM) and UV- visible spectroscopy. The
XRD results showed that ZnO has hexagonal wurtzite structure and
the Fe ions were well incorporated into the ZnO structure. As the Fe
level increased from 2 wt% to 8 wt%, the crystallite size reduced in
comparison with the pure ZnO. The transmittance spectra were then
recorded at wavelengths ranging from 300 nm to 1000 nm. The
optical band gap energy of spin-coated films also decreased as Fe
doping concentra
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The present study was investigated the activity of aqueous extract from Cinnamomum cassia bark on the blood glucose levels in healthy and diabetic rats induced by Streptozotcin (STZ). In healthy rats the blood glucose levels were slightly decreased after six hoursof single oral administration with dose (25 mg/kg) of body wight, as well as four weeks after twice daily repeated oral administration of aqueous extract of Cinnamomum cassia bark. In streptozotocin induced diabetic rats we absorved high significant decreased (p<0.05) in blood glucose levels, after four weeks of oral administration of aqueous extract (25 mg /kg ).And blood glucose levels seems to be normal after the period of treatment .Glibenclamide used as standard drug to com
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Sixteen new complexes with the general formula [M(L)2(H2O)2] were prepared resulting from the reaction of the two new Schiff base ligands, which are: - L1= (E)-5-((2-hydroxybenzylidene)amino)-2-phenyl-2,4-dihydro-3H-pyrazol-3-one) L2 = (E)-5-((2-hydroxy-3-methoxybenzylidene)amino)-2-phenylpyrazolidin-3-one) With divalent metal ions (manganese, cobalt, nickel, copper, zinc, cadmium, mercury) and (tetravalent platinum). Ligands was derived from the reaction of the amine (5-amino-2-phenyl-2,4-dihydro-3H-pyrazol-3-one) with Salicylaldehyde and ortho-vanillin, which is linked to the metal ions via the nitrogen atoms are the isomethene group and the oxygen is the hydroxide group of t
... Show MoreCampsis grandiflora (Bignoniaceae) is a fast growing deciduous climber, the dried flowers have been used as a carminative, blood tonic, and febrifuge in Chinese traditional medicine. This plant has an anti-inflammatory, anti-oxidant, anti-depressant, and anti-bacterial effect; with a beneficial role in stagnant blood and endometriosis conditions. In this study, the detection of beta-sitosterol in the hexane extract of Iraqi C.grandiflora flowers was performed using thin layer chromatography (TLC) and high performance liquid chromatography(HPLC); while the isolation done by preparative layer chromatography then structure elucidation of isolated compound was done by FTIR and 1HNMR. Furthermore, assessment of th
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